Image file formats
نویسنده
چکیده
This tutorial is about image file formats: what are they, what are they used for, what are their differences and how we choose between them. The tutorial assumes a basic understanding of general digital imaging; of which a quick summary of important features is provided below. Pixel: a digital image is represented as a rectangular grid of dots, where each dot has a specific spatial position and is colour defined. Each of these dots is known as pixels, and represents the smallest unit in a digital image. Matrix Size: the dimensions of a digital image; usually specified in terms of its width and height in pixels. For an image with square pixels, the matrix size also works to define the image aspect ratio. Spatial Resolution: a measure of the amount of spatial detail in a digital image. Resolution is stated as a ratio of physical to sampled dimensions, usually in the form of pixels per cm or dots per inch. The stated physical dimensions depend on whether the application is for acquisition or output. Colour Space: colour space or colour specification system is the method used to represent colour. Greyscale or monochrome images usually use a single intensity gradient. Colour images however, often encode colour in multiple channels, combining them to represent an individual colour. Common examples include RedGreen-Blue (RGB) and Cyan-Magenta-Yellow-Black (CMYK). Bit Depth: bit or colour depth may be thought of as colour resolution, i.e., a measure of the amount of colour
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Standardizing file formats, security, and integration of digital chest image files for pneumoconiosis classification
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